xfs: define the on-disk refcount btree format
Start constructing the refcount btree implementation by establishing
the on-disk format and everything needed to read, write, and
manipulate the refcount btree blocks.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff --git a/fs/xfs/Makefile b/fs/xfs/Makefile
index 584e87e..8d749f2 100644
--- a/fs/xfs/Makefile
+++ b/fs/xfs/Makefile
@@ -55,6 +55,7 @@
xfs_ag_resv.o \
xfs_rmap.o \
xfs_rmap_btree.o \
+ xfs_refcount_btree.o \
xfs_sb.o \
xfs_symlink_remote.o \
xfs_trans_resv.o \
diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index f8bab9b..5c8e6f2 100644
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -1217,6 +1217,9 @@
case XFS_BTNUM_RMAP:
xfs_buf_set_ref(bp, XFS_RMAP_BTREE_REF);
break;
+ case XFS_BTNUM_REFC:
+ xfs_buf_set_ref(bp, XFS_REFC_BTREE_REF);
+ break;
default:
ASSERT(0);
}
diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index e7ef1d9..c2b01d1c 100644
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -49,6 +49,7 @@
struct xfs_inobt_key inobt;
struct xfs_rmap_key rmap;
struct xfs_rmap_key __rmap_bigkey[2];
+ struct xfs_refcount_key refc;
};
union xfs_btree_rec {
@@ -57,6 +58,7 @@
struct xfs_alloc_rec alloc;
struct xfs_inobt_rec inobt;
struct xfs_rmap_rec rmap;
+ struct xfs_refcount_rec refc;
};
/*
@@ -221,6 +223,15 @@
struct xfs_bmbt_irec b;
struct xfs_inobt_rec_incore i;
struct xfs_rmap_irec r;
+ struct xfs_refcount_irec rc;
+};
+
+/* Per-AG btree private information. */
+union xfs_btree_cur_private {
+ struct {
+ unsigned long nr_ops; /* # record updates */
+ int shape_changes; /* # of extent splits */
+ } refc;
};
/*
@@ -247,6 +258,7 @@
struct xfs_buf *agbp; /* agf/agi buffer pointer */
struct xfs_defer_ops *dfops; /* deferred updates */
xfs_agnumber_t agno; /* ag number */
+ union xfs_btree_cur_private priv;
} a;
struct { /* needed for BMAP */
struct xfs_inode *ip; /* pointer to our inode */
diff --git a/fs/xfs/libxfs/xfs_format.h b/fs/xfs/libxfs/xfs_format.h
index 622055b..97c74f4 100644
--- a/fs/xfs/libxfs/xfs_format.h
+++ b/fs/xfs/libxfs/xfs_format.h
@@ -1457,6 +1457,42 @@
unsigned int xfs_refc_block(struct xfs_mount *mp);
+/*
+ * Data record/key structure
+ *
+ * Each record associates a range of physical blocks (starting at
+ * rc_startblock and ending rc_blockcount blocks later) with a reference
+ * count (rc_refcount). Extents that are being used to stage a copy on
+ * write (CoW) operation are recorded in the refcount btree with a
+ * refcount of 1. All other records must have a refcount > 1 and must
+ * track an extent mapped only by file data forks.
+ *
+ * Extents with a single owner (attributes, metadata, non-shared file
+ * data) are not tracked here. Free space is also not tracked here.
+ * This is consistent with pre-reflink XFS.
+ */
+struct xfs_refcount_rec {
+ __be32 rc_startblock; /* starting block number */
+ __be32 rc_blockcount; /* count of blocks */
+ __be32 rc_refcount; /* number of inodes linked here */
+};
+
+struct xfs_refcount_key {
+ __be32 rc_startblock; /* starting block number */
+};
+
+struct xfs_refcount_irec {
+ xfs_agblock_t rc_startblock; /* starting block number */
+ xfs_extlen_t rc_blockcount; /* count of free blocks */
+ xfs_nlink_t rc_refcount; /* number of inodes linked here */
+};
+
+#define MAXREFCOUNT ((xfs_nlink_t)~0U)
+#define MAXREFCEXTLEN ((xfs_extlen_t)~0U)
+
+/* btree pointer type */
+typedef __be32 xfs_refcount_ptr_t;
+
/*
* BMAP Btree format definitions
diff --git a/fs/xfs/libxfs/xfs_refcount_btree.c b/fs/xfs/libxfs/xfs_refcount_btree.c
new file mode 100644
index 0000000..359cf0c
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_refcount_btree.c
@@ -0,0 +1,178 @@
+/*
+ * Copyright (C) 2016 Oracle. All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_shared.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_sb.h"
+#include "xfs_mount.h"
+#include "xfs_btree.h"
+#include "xfs_bmap.h"
+#include "xfs_refcount_btree.h"
+#include "xfs_alloc.h"
+#include "xfs_error.h"
+#include "xfs_trace.h"
+#include "xfs_cksum.h"
+#include "xfs_trans.h"
+#include "xfs_bit.h"
+
+static struct xfs_btree_cur *
+xfs_refcountbt_dup_cursor(
+ struct xfs_btree_cur *cur)
+{
+ return xfs_refcountbt_init_cursor(cur->bc_mp, cur->bc_tp,
+ cur->bc_private.a.agbp, cur->bc_private.a.agno,
+ cur->bc_private.a.dfops);
+}
+
+STATIC bool
+xfs_refcountbt_verify(
+ struct xfs_buf *bp)
+{
+ struct xfs_mount *mp = bp->b_target->bt_mount;
+ struct xfs_btree_block *block = XFS_BUF_TO_BLOCK(bp);
+ struct xfs_perag *pag = bp->b_pag;
+ unsigned int level;
+
+ if (block->bb_magic != cpu_to_be32(XFS_REFC_CRC_MAGIC))
+ return false;
+
+ if (!xfs_sb_version_hasreflink(&mp->m_sb))
+ return false;
+ if (!xfs_btree_sblock_v5hdr_verify(bp))
+ return false;
+
+ level = be16_to_cpu(block->bb_level);
+ if (pag && pag->pagf_init) {
+ if (level >= pag->pagf_refcount_level)
+ return false;
+ } else if (level >= mp->m_refc_maxlevels)
+ return false;
+
+ return xfs_btree_sblock_verify(bp, mp->m_refc_mxr[level != 0]);
+}
+
+STATIC void
+xfs_refcountbt_read_verify(
+ struct xfs_buf *bp)
+{
+ if (!xfs_btree_sblock_verify_crc(bp))
+ xfs_buf_ioerror(bp, -EFSBADCRC);
+ else if (!xfs_refcountbt_verify(bp))
+ xfs_buf_ioerror(bp, -EFSCORRUPTED);
+
+ if (bp->b_error) {
+ trace_xfs_btree_corrupt(bp, _RET_IP_);
+ xfs_verifier_error(bp);
+ }
+}
+
+STATIC void
+xfs_refcountbt_write_verify(
+ struct xfs_buf *bp)
+{
+ if (!xfs_refcountbt_verify(bp)) {
+ trace_xfs_btree_corrupt(bp, _RET_IP_);
+ xfs_buf_ioerror(bp, -EFSCORRUPTED);
+ xfs_verifier_error(bp);
+ return;
+ }
+ xfs_btree_sblock_calc_crc(bp);
+
+}
+
+const struct xfs_buf_ops xfs_refcountbt_buf_ops = {
+ .name = "xfs_refcountbt",
+ .verify_read = xfs_refcountbt_read_verify,
+ .verify_write = xfs_refcountbt_write_verify,
+};
+
+static const struct xfs_btree_ops xfs_refcountbt_ops = {
+ .rec_len = sizeof(struct xfs_refcount_rec),
+ .key_len = sizeof(struct xfs_refcount_key),
+
+ .dup_cursor = xfs_refcountbt_dup_cursor,
+ .buf_ops = &xfs_refcountbt_buf_ops,
+};
+
+/*
+ * Allocate a new refcount btree cursor.
+ */
+struct xfs_btree_cur *
+xfs_refcountbt_init_cursor(
+ struct xfs_mount *mp,
+ struct xfs_trans *tp,
+ struct xfs_buf *agbp,
+ xfs_agnumber_t agno,
+ struct xfs_defer_ops *dfops)
+{
+ struct xfs_agf *agf = XFS_BUF_TO_AGF(agbp);
+ struct xfs_btree_cur *cur;
+
+ ASSERT(agno != NULLAGNUMBER);
+ ASSERT(agno < mp->m_sb.sb_agcount);
+ cur = kmem_zone_zalloc(xfs_btree_cur_zone, KM_NOFS);
+
+ cur->bc_tp = tp;
+ cur->bc_mp = mp;
+ cur->bc_btnum = XFS_BTNUM_REFC;
+ cur->bc_blocklog = mp->m_sb.sb_blocklog;
+ cur->bc_ops = &xfs_refcountbt_ops;
+
+ cur->bc_nlevels = be32_to_cpu(agf->agf_refcount_level);
+
+ cur->bc_private.a.agbp = agbp;
+ cur->bc_private.a.agno = agno;
+ cur->bc_private.a.dfops = dfops;
+ cur->bc_flags |= XFS_BTREE_CRC_BLOCKS;
+
+ cur->bc_private.a.priv.refc.nr_ops = 0;
+ cur->bc_private.a.priv.refc.shape_changes = 0;
+
+ return cur;
+}
+
+/*
+ * Calculate the number of records in a refcount btree block.
+ */
+int
+xfs_refcountbt_maxrecs(
+ struct xfs_mount *mp,
+ int blocklen,
+ bool leaf)
+{
+ blocklen -= XFS_REFCOUNT_BLOCK_LEN;
+
+ if (leaf)
+ return blocklen / sizeof(struct xfs_refcount_rec);
+ return blocklen / (sizeof(struct xfs_refcount_key) +
+ sizeof(xfs_refcount_ptr_t));
+}
+
+/* Compute the maximum height of a refcount btree. */
+void
+xfs_refcountbt_compute_maxlevels(
+ struct xfs_mount *mp)
+{
+ mp->m_refc_maxlevels = xfs_btree_compute_maxlevels(mp,
+ mp->m_refc_mnr, mp->m_sb.sb_agblocks);
+}
diff --git a/fs/xfs/libxfs/xfs_refcount_btree.h b/fs/xfs/libxfs/xfs_refcount_btree.h
new file mode 100644
index 0000000..9e9ad7c
--- /dev/null
+++ b/fs/xfs/libxfs/xfs_refcount_btree.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2016 Oracle. All Rights Reserved.
+ *
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+#ifndef __XFS_REFCOUNT_BTREE_H__
+#define __XFS_REFCOUNT_BTREE_H__
+
+/*
+ * Reference Count Btree on-disk structures
+ */
+
+struct xfs_buf;
+struct xfs_btree_cur;
+struct xfs_mount;
+
+/*
+ * Btree block header size
+ */
+#define XFS_REFCOUNT_BLOCK_LEN XFS_BTREE_SBLOCK_CRC_LEN
+
+/*
+ * Record, key, and pointer address macros for btree blocks.
+ *
+ * (note that some of these may appear unused, but they are used in userspace)
+ */
+#define XFS_REFCOUNT_REC_ADDR(block, index) \
+ ((struct xfs_refcount_rec *) \
+ ((char *)(block) + \
+ XFS_REFCOUNT_BLOCK_LEN + \
+ (((index) - 1) * sizeof(struct xfs_refcount_rec))))
+
+#define XFS_REFCOUNT_KEY_ADDR(block, index) \
+ ((struct xfs_refcount_key *) \
+ ((char *)(block) + \
+ XFS_REFCOUNT_BLOCK_LEN + \
+ ((index) - 1) * sizeof(struct xfs_refcount_key)))
+
+#define XFS_REFCOUNT_PTR_ADDR(block, index, maxrecs) \
+ ((xfs_refcount_ptr_t *) \
+ ((char *)(block) + \
+ XFS_REFCOUNT_BLOCK_LEN + \
+ (maxrecs) * sizeof(struct xfs_refcount_key) + \
+ ((index) - 1) * sizeof(xfs_refcount_ptr_t)))
+
+extern struct xfs_btree_cur *xfs_refcountbt_init_cursor(struct xfs_mount *mp,
+ struct xfs_trans *tp, struct xfs_buf *agbp, xfs_agnumber_t agno,
+ struct xfs_defer_ops *dfops);
+extern int xfs_refcountbt_maxrecs(struct xfs_mount *mp, int blocklen,
+ bool leaf);
+extern void xfs_refcountbt_compute_maxlevels(struct xfs_mount *mp);
+
+#endif /* __XFS_REFCOUNT_BTREE_H__ */
diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c
index 4aecc5f..a70aec9 100644
--- a/fs/xfs/libxfs/xfs_sb.c
+++ b/fs/xfs/libxfs/xfs_sb.c
@@ -38,6 +38,8 @@
#include "xfs_ialloc_btree.h"
#include "xfs_log.h"
#include "xfs_rmap_btree.h"
+#include "xfs_bmap.h"
+#include "xfs_refcount_btree.h"
/*
* Physical superblock buffer manipulations. Shared with libxfs in userspace.
@@ -737,6 +739,13 @@
mp->m_rmap_mnr[0] = mp->m_rmap_mxr[0] / 2;
mp->m_rmap_mnr[1] = mp->m_rmap_mxr[1] / 2;
+ mp->m_refc_mxr[0] = xfs_refcountbt_maxrecs(mp, sbp->sb_blocksize,
+ true);
+ mp->m_refc_mxr[1] = xfs_refcountbt_maxrecs(mp, sbp->sb_blocksize,
+ false);
+ mp->m_refc_mnr[0] = mp->m_refc_mxr[0] / 2;
+ mp->m_refc_mnr[1] = mp->m_refc_mxr[1] / 2;
+
mp->m_bsize = XFS_FSB_TO_BB(mp, 1);
mp->m_ialloc_inos = (int)MAX((__uint16_t)XFS_INODES_PER_CHUNK,
sbp->sb_inopblock);
diff --git a/fs/xfs/libxfs/xfs_shared.h b/fs/xfs/libxfs/xfs_shared.h
index 0c5b30b..c6f4eb4 100644
--- a/fs/xfs/libxfs/xfs_shared.h
+++ b/fs/xfs/libxfs/xfs_shared.h
@@ -39,6 +39,7 @@
extern const struct xfs_buf_ops xfs_agfl_buf_ops;
extern const struct xfs_buf_ops xfs_allocbt_buf_ops;
extern const struct xfs_buf_ops xfs_rmapbt_buf_ops;
+extern const struct xfs_buf_ops xfs_refcountbt_buf_ops;
extern const struct xfs_buf_ops xfs_attr3_leaf_buf_ops;
extern const struct xfs_buf_ops xfs_attr3_rmt_buf_ops;
extern const struct xfs_buf_ops xfs_bmbt_buf_ops;
@@ -122,6 +123,7 @@
#define XFS_INO_REF 2
#define XFS_ATTR_BTREE_REF 1
#define XFS_DQUOT_REF 1
+#define XFS_REFC_BTREE_REF 1
/*
* Flags for xfs_trans_ichgtime().
diff --git a/fs/xfs/libxfs/xfs_trans_resv.c b/fs/xfs/libxfs/xfs_trans_resv.c
index 301ef2f..7c840e1 100644
--- a/fs/xfs/libxfs/xfs_trans_resv.c
+++ b/fs/xfs/libxfs/xfs_trans_resv.c
@@ -73,7 +73,7 @@
*
* Keep in mind that max depth is calculated separately for each type of tree.
*/
-static uint
+uint
xfs_allocfree_log_count(
struct xfs_mount *mp,
uint num_ops)
diff --git a/fs/xfs/libxfs/xfs_trans_resv.h b/fs/xfs/libxfs/xfs_trans_resv.h
index 0eb46ed..36a1511 100644
--- a/fs/xfs/libxfs/xfs_trans_resv.h
+++ b/fs/xfs/libxfs/xfs_trans_resv.h
@@ -102,5 +102,6 @@
#define XFS_ATTRRM_LOG_COUNT 3
void xfs_trans_resv_calc(struct xfs_mount *mp, struct xfs_trans_resv *resp);
+uint xfs_allocfree_log_count(struct xfs_mount *mp, uint num_ops);
#endif /* __XFS_TRANS_RESV_H__ */
diff --git a/fs/xfs/xfs_mount.c b/fs/xfs/xfs_mount.c
index 56e85a6..3f64615 100644
--- a/fs/xfs/xfs_mount.c
+++ b/fs/xfs/xfs_mount.c
@@ -43,6 +43,7 @@
#include "xfs_icache.h"
#include "xfs_sysfs.h"
#include "xfs_rmap_btree.h"
+#include "xfs_refcount_btree.h"
static DEFINE_MUTEX(xfs_uuid_table_mutex);
@@ -684,6 +685,7 @@
xfs_bmap_compute_maxlevels(mp, XFS_ATTR_FORK);
xfs_ialloc_compute_maxlevels(mp);
xfs_rmapbt_compute_maxlevels(mp);
+ xfs_refcountbt_compute_maxlevels(mp);
xfs_set_maxicount(mp);
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 8fab496..0be14a7 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -124,10 +124,13 @@
uint m_inobt_mnr[2]; /* min inobt btree records */
uint m_rmap_mxr[2]; /* max rmap btree records */
uint m_rmap_mnr[2]; /* min rmap btree records */
+ uint m_refc_mxr[2]; /* max refc btree records */
+ uint m_refc_mnr[2]; /* min refc btree records */
uint m_ag_maxlevels; /* XFS_AG_MAXLEVELS */
uint m_bm_maxlevels[2]; /* XFS_BM_MAXLEVELS */
uint m_in_maxlevels; /* max inobt btree levels. */
uint m_rmap_maxlevels; /* max rmap btree levels */
+ uint m_refc_maxlevels; /* max refcount btree level */
xfs_extlen_t m_ag_prealloc_blocks; /* reserved ag blocks */
uint m_alloc_set_aside; /* space we can't use */
uint m_ag_max_usable; /* max space per AG */
diff --git a/fs/xfs/xfs_ondisk.h b/fs/xfs/xfs_ondisk.h
index 69e2986..0c381d7 100644
--- a/fs/xfs/xfs_ondisk.h
+++ b/fs/xfs/xfs_ondisk.h
@@ -49,6 +49,8 @@
XFS_CHECK_STRUCT_SIZE(struct xfs_dsymlink_hdr, 56);
XFS_CHECK_STRUCT_SIZE(struct xfs_inobt_key, 4);
XFS_CHECK_STRUCT_SIZE(struct xfs_inobt_rec, 16);
+ XFS_CHECK_STRUCT_SIZE(struct xfs_refcount_key, 4);
+ XFS_CHECK_STRUCT_SIZE(struct xfs_refcount_rec, 12);
XFS_CHECK_STRUCT_SIZE(struct xfs_rmap_key, 20);
XFS_CHECK_STRUCT_SIZE(struct xfs_rmap_rec, 24);
XFS_CHECK_STRUCT_SIZE(struct xfs_timestamp, 8);
@@ -56,6 +58,7 @@
XFS_CHECK_STRUCT_SIZE(xfs_alloc_ptr_t, 4);
XFS_CHECK_STRUCT_SIZE(xfs_alloc_rec_t, 8);
XFS_CHECK_STRUCT_SIZE(xfs_inobt_ptr_t, 4);
+ XFS_CHECK_STRUCT_SIZE(xfs_refcount_ptr_t, 4);
XFS_CHECK_STRUCT_SIZE(xfs_rmap_ptr_t, 4);
/* dir/attr trees */
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 8446338..c7b9853 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -39,16 +39,7 @@
struct xfs_inode_log_format;
struct xfs_bmbt_irec;
struct xfs_btree_cur;
-
-#ifndef XFS_REFCOUNT_IREC_PLACEHOLDER
-#define XFS_REFCOUNT_IREC_PLACEHOLDER
-/* Placeholder definition to avoid breaking bisectability. */
-struct xfs_refcount_irec {
- xfs_agblock_t rc_startblock; /* starting block number */
- xfs_extlen_t rc_blockcount; /* count of free blocks */
- xfs_nlink_t rc_refcount; /* number of inodes linked here */
-};
-#endif
+struct xfs_refcount_irec;
DECLARE_EVENT_CLASS(xfs_attr_list_class,
TP_PROTO(struct xfs_attr_list_context *ctx),